hi OPsorry to be dense, but how does it relate to your arthritis - will it be more painful on a fast day?

I am not hugely convinced that you will get benefits of fasting if you effectively drip feed yourself.

I don't "do" recipes on a fast day. I guess if I was splitting calories I'd have a bit of yogurt, maybe oatcake with hummus and then a tomato juice or some broth based soup?

I found this para on 5:2 and diabetes

*Type 2 diabetes and the 5:2 fast diet

The fact that intermittent fasting shows evidence of improving insulin sensitivity may be an attractive option for people with a BMI over 25, borderline diabetes (prediabetes) or with type 2 diabetes but not on blood sugar-lowering medications.

The diet may be good for people who can handle single days of significantly restricted calorie intake in preference to modest calorie restriction every day.

On fasting days, the body will be forced to use stored energy from the body, fat and stored sugar (glycogen), which can help with weight loss and may improve blood glucose and cholesterol levels.

If you are on insulin, or hypo causing medication, such as sulphonylureas or glinides, an intermittent fasting could significantly increase the risk of hypos. Your doctor should advise you on whether the diet is appropriate.*

Don't worry about not being able to exercise: Diet really is 80-90% of weight loss, even for gym rats.Losing weight should relieve the loading on your joints and reduce pain. Also, reducing body fat may reduce inflammation.

I'm a scientist and have examined many peer-reviewed papers on fasting. It is best to examine the science rather than speculate as a layman.

Studies have shown that you should gain the fasting benefits whatever your meal distribution, provided you remain within the 500 total calories, e.g. Varady et al Journal Obesity

Since your GP has cleared you to try fasting, they are presumably not concerned about hypos in your case.

Weight loss averaging 15kg (2 stone 5lb) achieved over 8 weeks caused two distinct sets of changes:1) Within 7 days, liver fat had fallen by 30%, liver insulin sensitivity had returned to normal and fasting blood glucose had become normal. 2) By 8 weeks, pancreas fat content had returned to normal and insulin secretion by the pancreas had returned to normal.